Comprehensive CMR evaluation including 4D flow-derived E/A vorticity ratio in overweight adults with and without type...

This study aimed to assess the impacts of overweight and type 2 diabetes (T2D) on early hemodynamic and left ventricular (LV) changes using comprehensive cardiovascular magnetic resonance imaging (CMR) in three age- and sex-similar groups: lean individuals (LI group), BMI-similar overweight controls without T2D (CWO group) and overweight individuals with uncomplicated T2D (T2D group).

Middle-aged participants included 13 in the LI group, 37 in the CWO group, and 28 in the T2D group. Baseline assessments included cardiac and vascular function measured by CMR, thoracic echocardiography, insulin sensitivity, clinical measures, and cardiorespiratory fitness. 4D flow CMR was used to evaluate diastolic function via valve tracking and intraventricular flow analysis. Group differences were analyzed using ANOVA or Kruskal-Wallis tests, with Holm-Bonferroni correction applied for pairwise comparisons. Linear correlation and multivariate regression analyses were performed to evaluate the associations between CMR-derived diastolic variables and echocardiographic and clinical measures.

Cardiorespiratory fitness was significantly lower in both the CWO and T2D groups compared with the LI group (all P < 0.001), with no difference between CWO and T2D. 4D flow CMR identified significant differences in the E/A velocity ratio between LI and CWO groups (P = 0.029), and in E/A velocity, flow, and vorticity ratios between CWO and T2D groups (P = 0.025, 0.031, and 0.034, respectively). The E/A vorticity ratio correlated moderately with conventional echocardiographic diastolic indices, such as MV E/A velocity ratio (Spearman's rho = 0.35, 95% CI: 0.07-0.60, P = 0.010; adjusted for age and sex). In multivariate regression, age (β =  - 0.014, P = 0.001), hypertension (β =  - 0.130, P = 0.015), heart rate (β =  - 0.009, P = 0.001), and circumferential peak early diastolic strain rate (β = 0.431, P = 0.002) emerged as independent determinants of the E/A vorticity ratio.

The present study suggests that the 4D flow CMR-derived E/A vorticity ratio may serve as a potential LV diastolic biomarker, given its capability in differentiating T2D-specific changes and stronger associations with clinical measures as well as CMR and echocardiographic parameters.

gov Identifier: NCT03419195 and NCT04791371.